Smoking has been determined to be the cause of approximately 30% of all cancer deaths. But it is very hard to stop smoking and only a fraction of the individuals who try succeed. In recent years the use of nicotine-containing chewing gums has been found beneficial in smoking cessation programs. These formulations separate the psychological aspects of addiction from the physiological aspects and allow each to be treated in turn. However, they have some side effects, do not maintain a constant blood level of nicotine, and permit the dosage of nicotine to be controlled by the patient rather than the physician. We propose to develop a controlled release transdermal nicotine delivery system. This system would deliver the drug at a continuous constant rate for twenty-four hours, after which it would be replaced with a fresh device. It would have an area of less than 20 cm2, and preferably as small as 10 cm2. in the proposed Phase I program, the system's feasibility would be demonstrated, and prototype devices prepared. The drug delivery rate from these devices and permeability of shaved rat skins to nicotine would be measured in vitro. In a subsequent Phase II program, the device design would be optimized and animal and clinical studies performed.